324 Jacob Parsons Schaeffer. 
Fig. 5 (x 4). Drawings of the mucous membrane, representing the exact 
shapes of the sinus maxillaris at different stages of its development in the fetus 
and child. 
A. From a fetus aged 4 months. B. From a fetus at term. C. From a child 
aged 18 to 20 months. D. From a child aged 20 to 23 months. 
ee en 
